Experiments in Metal Clay using Traditional Jewelry Working Techniques - Making a tounge clasp

I have made this pendant in PMC with an enameled center. I am going to string it on some Turquoise beads. I want a custom clasp on it so, I have decided to make a matching tongue clasp.
I made two boxes in PMC. One will be the receiver for the tongue clasp and the other will act as the tongue. I want the button, that works the clasp, to mimic a Turquoise bead.  The button will hover over the two textured boxes. This is a photo of the un-fired box that has the tongue attached to it.
I used 26 gauge sterling silver  and fabricated the tongue. It must be made from sterling silver instead of PMC because PMC would be too soft. I depleted the sterling silver sheet and formed it into the clasp. I attached the tongue to one of the carved boxes. Attached the PMC button onto the sterling silver tongue. Now I need to fire (sinter) it. This is the experiment part. By completing depletion on the sterling silver, will it hold in the PMC? Will the PMC box hold its shape when it shrinks? Or will the sterling silver cause it to warp? Will be bond on the button and tongue be strong enough?
Here is a side view of the tongue box. I will post the outcome shortly!!